120Adapter.Mk2.scad

//MKII adaptor for 120mm fan
$fn = 100;
//You can adjust the two variables below
depth = 40; //depth of air chamber (40)
hole = 4; //fan screw holes (4)
difference()
{
	union()
	{
		//baseplate
		hull()
		{
			for (i = [0: 90: 330]) rotate([0, 0, i])
			{
				translate([74, 0, 0])
				cylinder(h = 1.5, d1 = 15, d2 = 15);
			}
		}
		//Main outer cylinder
		cylinder(h = depth, d1 = 120, d2 = 120);
	}
	//internal cylinder
	translate([0, 0, -1])
	cylinder(h = depth + 2, d1 = 118, d2 = 118);
	//screw holes
	for (i = [0: 90: 330]) rotate([0, 0, i])
	{
		translate([74.5, 0, -1])
		cylinder(h = 4, d1 = hole, d2 = hole);
	}
}

Legs.Mk2.scad

//MKII leg for 120mm fan
$fn = 100;
//You can adjust the two variables below
depth = 50; //height of leg
hole = 4; //screw holes
difference()
{
	union()
	{
		//Main outer cylinder
		cylinder(h = depth, d1 = 12, d2 = 12);
	}
	//internal cylinder
	translate([0, 0, 2])
	cylinder(h = depth + 2, d1 = 10, d2 = 8);
	translate([0, 0, -1])
	cylinder(h = 4, d1 = hole, d2 = hole);
	translate([0, 0, depth - 1])
	cylinder(h = 2, d1 = 10, d2 = 10);
}

Notes.md

MK1: https://www.youtube.com/watch?v=kK7sJq2E0bE

Mk3: https://www.youtube.com/watch?v=_UkzfByvKrw

Platen.Mk3.scad

//MK3 platen for filter paper on 120mm fan
$fn = 100;
//You can adjust the variables below
depth = 10; //depth of lip and fins (10)
platen = 1.5; //thickness of platen (1.5)
//don't adjust anything below here
hole = platen + 2;
difference()
{
	union()
	{
		//platen
		cylinder(h = platen, d1 = 140, d2 = 140);
		//Main outer cylinder
		cylinder(h = depth + platen, d1 = 118, d2 = 118);
	}
	//internal cylinder
	translate([0, 0, platen])
	cylinder(h = depth + platen, d1 = 116, d2 = 116);
	//filter hole pattern
	for (i = [0: 45: 330]) rotate([0, 0, i])
	{
		translate([35, 0, -1])
		cylinder(h = hole, d1 = 20, d2 = 20);
		translate([16, 0, -1])
		cylinder(h = hole, d1 = 10, d2 = 10);
	}
	for (i = [22.5: 45: 350]) rotate([0, 0, i])
	{
		translate([24, 0, -1])
		cylinder(h = hole, d1 = 10, d2 = 10);
		translate([41, 0, -1])
		cylinder(h = hole, d1 = 10, d2 = 10);
		translate([32.5, 0, -1])
		cylinder(h = hole, d1 = 5, d2 = 5);
	}
	translate([0, 0, -1])
	cylinder(h = hole, d1 = 20, d2 = 20);
}
//anti turbulence fins
difference()
{
	for (i = [0: 45: 330]) rotate([0, 0, i])
	{
		translate([46, -0.5, 0])
		cube([12, 1, depth + platen]);
	}
}

WeightedRing.scad

//Weighted ring for paper
$fn = 100;
//The variables below can be adjusted if desired
depth = 2; //depth (weight) of ring
inner = 100; //inner hole diameter of ring
outer = 140; //outer diameter of ring
difference()
{
	union()
	{
		//main disk
		cylinder(h = depth, d1 = outer, d2 = outer);
	}
	//hole in middle
	translate([0, 0, -1])
	cylinder(h = depth + 2, d1 = inner, d2 = inner);
}